Regarding point 1, there's a widespread view in the Bay Area that it's good to get a "fresh" perspective in companies that are toxic enough to continually burn

Regarding point 1, there's a widespread view in the Bay Area that it's good to get a "fresh" perspective in companies that are toxic enough to continually burn out employees, which is many companies, probably most. Furthermore, high turnover is very, very common in VC startups, including CEOs.